Documenting the paintings

Why facsimiles?

Photographs are rarely good enough to document the sorts of scenes which you find in Egyptian monuments. Yes, they give you a good idea of the wall, but they can never show enough detail for scholars. Because Egyptian wall art is fundamentally two-dimensional, it is possible to make facsimile copies of them and not lose too much of the spirit of the decoration (by way of contrast, imagine doing such a copy of an Old Master!). Photographs are an essential part of the process, but only part. They attempt to document the colour, but if there is no control over the colour reproduction, then it is not reliable. Also the cost of publishing colour photographs is becoming prohibitive, and it is usually only possible to include a small cross-section.

Much of what follows is taken from a paper I presented at the British Museum colloquium in July 1996. References to this and other published material are given at the end of this page. For how we make Wall Plans, see a separate page.

Making a facsimile

The most common method used for making facsimiles in Egypt today is to make a full size original on the wall, with all the necessary features and details. We do it as follows: a copy is made on transparent flexible plastic acetate film in sheet or roll form with a permanent marker pen of various thicknesses. This image is then copied in ink onto tracing paper or film, which is then taken back to the tomb and collated with the original.

The strengths of this method include the following: it can be carried out successfully by those who are not artists, so long as the epigrapher is technically competent at tracing and copying; it is cheap in the field; and it is possible to move from the original to the finished facsimile in the course of one season, depending on the inking method employed. Against it are a number of points: the danger of inaccuracy inherent in any copying process and the fact that copying copies compounds the chance of further errors; there is always a very small risk of damage to the wall from the contact between the surface and the copying material; and finally, the costs associated with printing.

An unexpected problem encountered with the publication of TT294, 253, and 254 was the cost of the origination of the line plates. These drawings were made at 100% size on rolls of tracing paper of variable length and 1016 mm (40 inches) in width, and it proved impossible for the printer to find a process camera which could photograph originals this size. They were eventually photographed in sections of approximately A2 size, and the resulting films were joined together, which required a cameraman of considerable skill to produce a seamless result. The labour cost of production of these reductions was thus high. I understand that cameras of larger sizes do exist in the UK, but are rare and extremely expensive. Is this an example where 'market forces' and the move to the European DIN standard actually reduces choice, in that unusual sizes are becoming harder to reproduce? Colleagues in the USA seem to have fewer problems finding suitable cameras.

Recording the colours

Black and white line art doesn't reproduce colours very well! The ideal best method would be the colour facsimile, such as those produced by Nina de Garis Davies between 1907 and 1940, and which can be seen in the Metropolitan Museum of Art, the Ashmolean Museum, and the British Museum. Finding an artist with the time and ability to do these today is very difficult however. So, what do we need and how can we do it today?

We need objective data which allows the colours to be formally quantified, and which then permits a user of the publication to compare the colours on the present monument with those from others, and if needed perform a statistical analysis to describe the similarity or difference. But we also need more subjective data, a colour illustration, which permits an immediate visual response to the perceived colours of the subject. The second is easy to solve, at least in theory, since the obvious method today is colour photography, although the practical side is anything but straightforward.

Taking a colour photograph suitable for a publication is not as easy as it may seem, and the best photographs are inevitably the result of the employment of a professional. But this is only the first stage, as the photographs are then passed on to the printer, where many further complications can arise.

A considerable amount of research has been undertaken in Europe during the 1990s by the MARC project (Methodology of Art Reproduction in Colour), with the aim of understanding and improving the reproduction of works of art in colour. While much of the work of this project so far has been concerned with Old Master paintings, there is much which ultimately may be of use to the documentation of Egyptian monuments.

Most of the epigrapher's concerns about colour photography come down to inaccurate or variable reproduction of the colours in the final publication. While there is no doubt that in some cases this is due to variability in the original photographs (and I do not excuse my own photographs in this respect), other problems can be introduced at the printing stage. One fundamental problem with colour printing is that most images are printed in the standard four process colours (CMYK: cyan, yellow, magenta, and black), and the combination of these four inks cannot reproduce every colour in a photograph or which the eye can see. So there is an element of compromise at the beginning, despite everything which the skill of the printer can do to minimise the problems. The colours can be corrected, but these adjustments tend to be of the type 'add more yellow', and each time require a proof to be produced, adding to the cost.

This is one of the paradoxes of colour reproduction for scholarly Egyptological books. Such books ideally need the most investment in the accuracy of the colours, but the financial constraints of the undertaking understandably have the last word and usually argue against more than one proof. Publications of Theban tombs typically have small print runs, usually in the region of 500 copies, and thus the expense of each colour correction has a significant effect on the unit cost. Books with a larger target audience and print run can more easily subsume the cost of colour correction, in the way that they can also justify the cost of more colour photographs in the first place. Nonetheless, researchers in the MARC project noted that even for fine art such corrections are often prohibitively expensive.

When or if digital printing becomes a reality, and finer colours and simpler corrections are possible, then some of these problems may disappear. Colour printing is not as expensive as it used to be, but it will remain feasible to include only a small number of colour illustrations in tomb publications for some time.

The use of colour photographs can at present only be a guide to the colours of the monument. This is a good reason for trying to supplement the impressions these photographs give with some more objective method.

Colour charts have been used sporadically by epigraphers for a number of years in an attempt to put the recording of the colouration of tomb scenes on an objective basis. While a commendable first step, the method errs in that there is an element of human subjectivity present, combined with inevitable variation in the viewing conditions. No object has an immutable 'colour'; only its physical composition and location are fixed. What we refer to as the 'colour' of something is more scientifically termed the 'stimulus for colour', and can be expressed by the equation

stimulus = light source x reflectance x observer response

From this it should be clear that it only needs a small variation in any of the three elements, typically a different light source or observer, to produce a different result, and that result is of course another colour.

One solution to these problems is to record the colour with a colourimeter, a device designed specifically to measure colours, having its own consistent sensors and light source. I have described the methods and problems associated with using such an instrument. There is still, however, some scepticism as to whether this is really more effective than using colour charts; Egyptologists are perhaps too ready to believe what their eyes seem to be telling them about colour, and too willing to think they can mentally correct the present state of a painted surface to its original hue.

The colourimeter can record data in a number of different ways, which allow it to be manipulated numerically (Yxy, see below) and related to visual standards (such as Munsell colour charts). This material is technically not difficult to publish, since it consists of a series of readings along with notes on the subject of the reading. However, a balance has to be struck between the amount of data and the tolerance of the reader or publisher. The solution I adopted was to list the Munsell values with notes and reference numbers, and indicate that the more technical readings are available for anyone who wishes to work with them.

The data from the colourimeter makes it possible to illustrate and group colours in ways not feasible before. The analyses in the publication of TT253, 254, and 294 show some possible approaches but are not exhaustive. The adjacent figures are 'chromaticity diagrams', using the x and y elements of the Yxy data. The first illustrates the male and female skin colours (using these terms to avoid using a specific subjective colour designation) in the rear room of TT99 from readings made in 1992. Each group clusters together closely, with very low standard deviations. This deliberately simple example does not tell us a great deal more than that the paint colour within the scenes is quite consistent, although that could in itself be significant. It is also a useful technique for isolating rogue readings, which can then be re-measured to see whether there was a problem in the recording or whether the original is indeed quite different. The other figure shows how this data can be combined with the same information from other tombs, in this case TT253 and 254.

The three tombs are respectively from the reigns of Thutmose III, Amenhotep III, and Tutankhamun or Ay. This is not the place for a full analysis of the implications of these diagrams, but it is evident that the colours in TT99 and TT253 relate more closely to each other than to TT254, and this could be used to show, for example, that the artists' palettes of the pre-Amarna period have more in common with each other than those employed at the end of the eighteenth dynasty.

I close the discussion of colour by reminding readers of one important point. Any system of recording colours can only record what is there now, which is inevitably affected by chemical change in the pigments, environmental factors, damage, and so on. How close this is to the originals is by no means clear.